Trial of Tadalafil, Tamsulosin and Combination for Access Sheath Deployment
Status:
Enrolling by invitation
Trial end date:
2022-04-01
Target enrollment:
Participant gender:
Summary
Extensive literature exists on the use of alpha-blocker medications for the removal of kidney
stones. Alpha blockers relax certain muscles and help small blood vessels remain open. They
work by keeping the hormone norepinephrine (noradrenaline) from tightening the muscles in the
walls of smaller arteries and veins, which causes the vessels to remain open and relaxed.
This improves blood flow and lowers blood pressure. There are studies that demonstrate
alpha-blockers decrease ureteral pressure and help the ureter "relax."
Recent studies have shown that phosphodiesterase inhibitors may also help with ureteral stone
passing. A phosphodiesterase inhibitor is a drug that blocks an enzyme that inhibits
relaxation of smooth muscle. This means that it can help smooth muscle, such as the muscle
that lines the ureter, to relax. While ureteral relaxation is helpful in the passage of
ureteral stones, our study seeks to use this finding by pretreating participants with an
older generation alpha blocker or a phosphodiesterase inhibitor prior to passage of a
ureteral access sheath in cases in which ureteroscopy is being used to approach a ureteral or
renal stone.
By relaxing the ureter, it is possible that a larger access sheath can be safely placed. This
may allow for facilitating passage of the ureteroscope and extraction of stone fragments
while precluding the development of potentially damaging intrarenal pressure from the flow of
irrigant. The ureteral access sheath also protects the ureter from damage during the
procedure. Placement of the largest access sheath possible is helpful in that larger stone
fragments can be retrieved, the flow of irrigant is improved, and the surgical field is kept
clear of blood or debris. To date, nobody has studied whether use of an uro-selective alpha
blocker, alone, or in combination with a 5 phosphodiesterase inhibitor will result in passage
of larger access sheaths.
In this study participants will be randomized into 1 of 4 categories: Flomax (alpha-blocker),
Cialis (5-phosphodiesterase inhibitor), a combination of the 2, or a placebo arm. In this
study the placebo, or no active drug, is the current standard of care and will serve as a
control from the other 3 groups.